Seo Min-Ho, Kim Bi-Na, Kim Kyoung-Rok, Lee Ki Won, Lee Choong-Hwan, Oh Deok-Kun
Department of Bioscience and Biotechnology, Konkuk University, Seoul, Republic of Korea.
Biosci Biotechnol Biochem. 2013;77(6):1245-50. doi: 10.1271/bbb.120899. Epub 2013 Jun 7.
Aspergillus oryzae KACC 40247 was selected from among 60 fungal strains as an effective 7,8,4'-trihydroxyisoflavone (8-hydroxydaidzein)-producing fungus. The optimal culture conditions for production by this strain in a 7-L fermentor were found to be 30 °C, pH 6, and 300 rpm. Under these conditions, A. oryzae KACC 40247 produced 62 mg/L of 8-hydroxydaidzein from soybean extract in 30 h, with a productivity of 2.1 mg/L/h. These are the highest production and productivity for 8-hydroxydaidzein ever reported. To increase production, several concentrations of daidzin and of daidzein as precursor were added at several culture times. The optimal addition time and concentration for daidzin were 12 h and 1,248 mg/L, and those for daidzein were 12 h and 254 mg/L respectively. Maximum production and productivity for 8-hydroxydaidzein with the addition of daidzein were 95 mg/L and 3.2 mg/L/h respectively, and those with the addition of daidzin were 160 mg/L and 4.4 mg/L/h respectively.
米曲霉KACC 40247是从60株真菌菌株中筛选出的一种能有效产生7,8,4'-三羟基异黄酮（8-羟基大豆苷元）的真菌。该菌株在7升发酵罐中生产的最佳培养条件为30℃、pH值6和300转/分钟。在这些条件下，米曲霉KACC 40247在30小时内从大豆提取物中产生了62毫克/升的8-羟基大豆苷元，生产率为2.1毫克/升/小时。这些是迄今报道的8-羟基大豆苷元的最高产量和生产率。为了提高产量，在几个培养时间点添加了几种浓度的大豆苷和大豆苷元作为前体。大豆苷的最佳添加时间和浓度分别为12小时和1248毫克/升，大豆苷元的最佳添加时间和浓度分别为12小时和254毫克/升。添加大豆苷元时8-羟基大豆苷元的最大产量和生产率分别为95毫克/升和3.2毫克/升/小时，添加大豆苷时分别为160毫克/升和4.4毫克/升/小时。
